I the reassembled the unit taking care in the postion of the pistons, springs solenoid piston (which must go back as it came out, look at the photos), submerged the whole thing in fresh oil for about 10mins, then bagged and tagged it.

I then repeated the same on Bank 2, this is bank 2 unit below:

http://986forum.com/forums/uploads02...1638116813.jpg

http://986forum.com/forums/uploads02...1638116865.jpg

Note that this configuration is not only different to bank 1 but there is an extra oilway at the top

http://986forum.com/forums/uploads02...1638116911.jpg

Once the unit was cleaned, it was primed, bagged and tag an back into storage with its sister. I wont know if it has improved things, though there was definitely and issue with contamination or killed the unit until I put the engine all back together, so I will update with observations then but hopefully at least the photos may help others

Now, I have an engineering background and looking at the unit, I feel it should be possible to refurbish it. The only inaccessible part is the central piston, which from what I have seen and feel must have some o-ring internally. There appears to be no way in as the circlip seems to be help in place by the tabs that have been flayed out in the photo below

http://986forum.com/forums/uploads02...1638117310.jpg

I can see there are no kits available to refurbish the unit, but I have purchased a second hand one to dismantle with a view of what is needed as there should be no reason why the metal cap in the photo cannot be reproduced. In any case, this is just an experiment and I will share my observations and findings in case it helps others :)

Cool stuff! You inspired me to purchase a can of carburetor cleaner, my souvenir piston from the rebuild of my 3.2 is soaking in it over the weekend. I'll see if I can get it close to how clean you got yours! But it still has the rings on and the wrist pin in.

Awesome :) If you are going to have it for show, then some Autosol will bring everything up and stop the rings from rusting

I can honestly say that my ultrasonic bath and small media blaster (using soda or fine glass beads) are outstanding in bringing things back to a near new look. Yes, you need to take care to use the right chems/media and clean thoroughly after using media but there is so much info/videos on the net that it really is not rocket science.

I am considering upgrading my small media blasting cabinet and buying a full on vapour blasting cabinet :)

I saw a video on Facebook of an auto detailing place, they were using a device that used dry ice in some kind of pressure washer. I think it is called a dry ice blaster. They were treating the undersides and inner fenders of cars with it and the parts were looking like new when they sprayed them. Remember, you can never be too rich, too thin, have too much horsepower or too many tools!

There's an article in Pedro's Garage about that.
Freeze your Road Grime!

Wow, thanks for sharing the link. I want one of those machines. :) Not only the car but I will do my neighbours cars, my house, their house, in fact anything else I can find to clean lol

It's called Dry Ice Blasting and has been around a long time in the metal working business. Here is a pretty good run down of what it is, how it works and what it is used for.

https://en.wikipedia.org/wiki/Dry-ice_blasting

The company I retired from is a primary supplier of the dry ice pellets to the industry.

This is one of my favourite parts of any rebuild, no matter what is being rebuilt. When parts start to arrive. For me, it really is like have lots of birthdays :)

Recently, we have 24 brand new, shiny lifters/tappets packed in oil

http://986forum.com/forums/uploads02...1638305141.jpg

A nice new oil separator with new gaskets

http://986forum.com/forums/uploads02...1638305170.jpg

And lots of other parts inc, new injectors, seals, bolts, screws, knock sensors, chains, guides, tensioner, etc. Its only a small portion and loads more on the way, but I like to buy things slowly and especially when I can gab a bargain. As with the injectors and lifters which I paid less than half the normal price for the same part.

http://986forum.com/forums/uploads02...1638305189.jpg

Hopefully the parts I need to start the bearing carrier rebuild will turn up soon

Great thread, thanks for sharing! The two variocam units are completely different, they move the chain to the opposite side during the changover. After browsing many threads and taking apart mine for inspection my understanding is that mostly only one of them fails, the one that has the large greenish O-rings that are prone to disintegrate due to aging. I forgot which one it is, I have a thread on this topic somewhere. Theoretically if you remove that steel cover disc you can pull the piston and replace the faulty O-rings. It does not seem to be easy to do though, it requires machining, mill, lathe, etc. If you go down that route let us know how it worked out. When I was rebuilding mine I tested the variocam operation while spinning the engine on my bench and activating the solenoids, and both turned out good. I have a thread on this in show & tell.

Good pictures, keep them coming! :cheers:

Awsm, thanks for sharing and I will definitely look up your thread.

I struggled to find any real description of the internals and also photos but lots of warnings and statements of “it can’t be done”, “non-serviceable” “cannot be refurbished” etc. I come from an engineering background and hearing that makes me think “really?” And makes me want to run an experiment to see why. Yes, once removed some parts cannot be reused, but with technology as it is today, such 3D-metal printing, CNC machines etc once we have a 3D model of the parts required then why cannot these non reusable parts be replaced? Maybe it’s cost, maybe it’s complexity, that’s the experiment I wish to run and I will share my observations not to encourage everyone not to replace with new Porsche parts but to share and document the observations for other :)

I have seen a European company that does produce reconditioned units so it must be possible

Actually, quick question for our community, it feels that the spring in the main piston has a different compression rating between each side. I need to check but from memory bank 2 was far easier to compress than bank 1. The difference being bank 2 could be compressed by hand and bank 1 required far more effort.

Does anyone have any similar experience/knowledge or observations?

Thanks in advance

I didn`t notice that, it`s possible though. Perhaps oil got trapped in one of the units and gave you you the impression it`s harder to compress? Bt, check out this thread, has pics of the internals of both actuators: http://986forum.com/forums/boxster-general-discussions/78048-boxster-986-particles-oil-filter-2.html

Hi Homeoboxter

Thanks, that is a very good point and I will check the deflection of each spring with a known load as its the only way to tell :)

Yes, it was that thread that encouraged me to look deeper into the units. Awesome information

Sweet, all the parts bar one that I need to start the bearing carrier rebuild turned up today (yes on a Sunday :))

Another birthday day lol

http://986forum.com/forums/uploads02...1638706163.jpg

Great thread! I'm subscribed.

Awesome thread. I'd love to rebuild a 3.4 for my Boxster but don't really have enough room. Maybe when both kids are out of the house.

And my last "part" arrived today so I can start my rebuild :)

http://986forum.com/forums/uploads02...1638976988.jpg

Have started with the clean up of the bottom end and will start sharing those photos and experiences and lessons learnt

After degreasing the crank and giving it a bath I checked the main journals and all were 60.0mm using a digital calliper. I have a micrometer somewhere and will dig it out to double check , but with all honesty I don’t know if this is good or bad.

Lots if posts from people have measured theirs but there appears to be nothing published as to factory spec by Porsche. Without buying a new crank, is anyone aware of the factory specs for both journals?

Porsche never published any internal clearance info on these engines as they didn't want anyone to work on them in the field. They didn't even publish engine internal torque specs. That is why Jake Raby's information is so important.

Thanks JFP in PA for confirming and replying, your help is very much welcome and appreciated. Got Jakes torque specs which is a God send as are his DVDs so far.

So the only way anyone can find out what the default factory spec for each journal is to buy a new crank and measure them and then publish them on the net to help others. Don’t really want to spend the money as my crank as far as I can see looks ok though I could be wrong as I don’t know what the original specs are :)

Nice (British sarcasm:))

A close approximation of the crank journal sizes could be obtained by torquing empty new bearing shells in the rod and mains carrier, then inside mic them.

Good call :)

It`s even easier to measure the clearance with plastigauge. You can check the old and new set and compare.

OldManMo you inspired me to clean up my souvenir piston from my engine before it was rebuilt as a 3.6. A week in a gallon of carburetor cleaner was all it took! Keep posting updates, I love following your progress!http://986forum.com/forums/uploads02...1639180880.jpg

So, my question is: how do you use this when the bolts have to be torqued and then taken to the proper angle--and are one-time use?

Easy: you use the old bolts for plastigauging/mic-ing and use the new ones for reassembly.

Thanks PaulE and others for the words of encouragement and really makes my day that I am helping others. My son and I are having lots of fun so far learning and seeing the progress. We had a great evening in the other day watching Jake’s DVDs with a bag of popcorn and a slushy. Me more than him mins you :)

Nothing so far has been daunting but that said I do believe I did the tear down at the right time before any damage.

Will share more progress in the next few days

Thank you all

So first round of cleaning for the carrier, crank and IMS

Before is yuk

http://986forum.com/forums/uploads02...1639414917.jpg

http://986forum.com/forums/uploads02...1639414956.jpg

http://986forum.com/forums/uploads02...1639414993.jpg

After is much better and can really see what the situation is. Still not finished with the carrier though

http://986forum.com/forums/uploads02...1639415041.jpg

http://986forum.com/forums/uploads02...1639415059.jpg

http://986forum.com/forums/uploads02...1639415123.jpg

http://986forum.com/forums/uploads02...1639415146.jpg

http://986forum.com/forums/uploads02...1639415177.jpg

Crank needs a little more work and I want a Machine Shop to check it. So will look to get it only micro polished

http://986forum.com/forums/uploads02...1639415086.jpg

I use an Ultrasonic bath to do the cleaning and interesting what you fine on the bottom. This is from the Crank, which wasnt bad even though its what is all that.

http://986forum.com/forums/uploads02...1639417351.jpg

I didnt take a picture after the carrier but there were loads of little bits of plastic once cleaning had finished

Brilliant, very interesting thread and how you document the progress. Thank you and keep up the fantastic work :cheers:

May I ask, the parts that where mediablasted, eg the gearbox. Did you clear coat them after? Any trick to make them stay that clean?

Hi Robert986

Different parts had a different finish. For the gearbox, I didn’t mediablast as it was too big for my machine, but I cleaned it with degreaser, then wire bushes, then used a lot of carb and brake cleaner, scotch pads, then I gave it a light coat of alloy wheel silver paint. One year it is still holding up. With hindsight, I probably sent this out to be media and vapour blasted then had a anti-corrosion coating applied.

For other parts such as suspension parts I did media blast with soda and fine glass beads (taken care for smooth finished areas) then applied either silver alloy paint or anti-corrosion coating. For the exhaust,, this was a couple of hours spent using a fine scotch brite wheel then a polishing wheel with a polishing compound like autosol

I need to do the front suspension and brakes so I will share what I do, again not to say this is the “right” way to do this but just what I did/do :)

Latest
 

Hi all

I know, its been ages. Lots of reasons, Christmas, holidays, work, home, waiting on parts, waiting on parts, waiting on funds and so on :)

Spent most of the time since my last post cleaning, measuring, investigating, learning while I waited to order and receive parts. I should hopefully be in a position to start the rebuild in the next month or so. Dont get me wrong, I currently have a small mountain of nice new engine parts, but still quite a bit more to get.

While cleaning the many parts in the ultrasonic tank, I could clearly see particulates fallen to bottom. These were mostly plastic from the chain guides and some pieces of carbon. There was however, lots of pieces and they came out from almost everything that was cleaned, Crank, Cams, lifters, lifter housing, IMS itself once the bearing was removed.

All honesty, I am not sure I didn't find lots of damage as it does look (and maybe I am fooling myself) as I caught it in time

So while I get ready to start the rebuild here is some photos from what has been done so far.

In almost all cases parts started in the tank, then cleaned and polished by hand, then back to the tank, then cleaned with carb cleaner, then back into the tank, then polished by hand again, then back to the tank...well you get it. BTW, I dont mind cleaning and polishing by hand, I find it therapeutic and I get up close and personal with the part

The IMS took lots of nice gentle work but ha come up nice. Lots of nasty sludge came out from the inside but more so when I used a bottle brush to get to the end

http://986forum.com/forums/uploads02...1645824365.jpg


http://986forum.com/forums/uploads02...1645824381.jpg

Will still go through one more round of cleaning before I fit it

Crank took some time also and I found a lot of sludge and a small piece of plastic in the oilways. The journals where hand polished. I used 10,000 grit wet and dry on the heavily soiled journals. The specs where in line with what is published else where on the net. It has been crack tested, but will have it tested once more and run through final cleaning just before fitting

This is how I started


http://986forum.com/forums/uploads02...1645824597.jpg

after a few round in the ultrasonic bath


http://986forum.com/forums/uploads02...1645824671.jpg

And a number of hours later by hand


http://986forum.com/forums/uploads02...1645824721.jpg


http://986forum.com/forums/uploads02...1645824741.jpg

Crank carrier also had the tank and hand polishing treatment. Had a strange one here as I reassembled without the bearing to torque to measure the roundness of the bearing seats and was seeing about 0.01-0.02mm differences across the face. I found that there were deposits of carbon/oil/stuff that I didn't notice the first time.

Spent some more time cleaning and polishing the seats and was seeing, sometimes only 0.01mm differences. Didn't think that the build up could be as much as that, but it could have dried on when I removed the bearing I guess.

You can see it a little in the phot below between the first seat on the left and the next ones

http://986forum.com/forums/uploads02...1645825008.jpg

The cams also had a thick (well less than 0.01mm) build up. Took a while and again by hand, though I did use a fine glass beads on shaft between the bearings and cams but they cam up nice


http://986forum.com/forums/uploads02...1645825159.jpg


http://986forum.com/forums/uploads02...1645825193.jpg


http://986forum.com/forums/uploads02...1645825217.jpg

lifter carrier also came up nice though this had a lot of deposits at the bottom of the ultrasonic bath when cleaned. Still needs a little more work and polishing


http://986forum.com/forums/uploads02...1645825292.jpg

lots of other parts scrubbed up well


http://986forum.com/forums/uploads02...1645825346.jpg


http://986forum.com/forums/uploads02...1645825383.jpg


http://986forum.com/forums/uploads02...1645825403.jpg

also got some new pistons

http://986forum.com/forums/uploads02...1645825462.jpg

And will be replacing the rod bushings as there was noticeable play and didn't like the look of them.

I assume these are pressed in as per normal, nothing special needed with them?


http://986forum.com/forums/uploads02...1645825555.jpg

Love watching the progress. What type of ultrasonic machine do you use?